Textile softener composition

ABSTRACT

This disclosure relates to a method and composition for imparting softness to textiles without yellowing by utilizing a borohydride-containing composition either in the form of a fabric-softening quaternary ammonium salt and an alkali metal borohydride or the corresponding qutarnary borohydride.

United States Patent Inventor Leo Thomas Murray East Brunswick, NJ.

Appl No. 686,756

Filed Nov. 29, 1967 Patented Nov. 16, 1971 Assignee Colgate-Palmolive Company New York, N.Y.

TEXTILE SOFTENER COMPOSITION [56] References Cited UNITED STATES PATENTS 3,081,265 3/1963 Burr 252/105 3,230,225 1/1966 Arrigo 260/567.6 X 3,296,144 1/1967 White 252/152 X Primary Examiner--Herbert B. Guynn Attorneys-Herbert S. Sylvester, Murray M. Grill, Norman Blumenkopf, Ronald S. Cornell, Thomas J. Corum, Richard N. Miller and Robert L. Stone ABSTRACT: This disclosure relates to a method and composition for imparting softness to textiles without yellowing by utilizing a borohydride-containing composition either in the form of a fabric-softening quaternary ammonium salt and an alkali metal borohydride or the corresponding qutarnary borohydride.

TEXTILE SOFTENER COMPOSITION The present invention relates to nonyellowing textile softener compositions containing a simple or complex borohydride.

Softening agents have been used in laundering in order to render fabrics or textiles soft, and the term softeningrefers to the handle, hand, touch or feel; this is the tactile impression given by textiles to the hand or body, and is of esthetic and commercial importance. Softening realized with such agents varies with a number of factors including: laundry load weight and composition, types of bleach use, if any, detergents used, the initial degree of harshness, type of washing machine, water temperature, etc. The most commonly used softening agents are cationic, such as the quaternary ammonium compounds because of their particular effectiveness. However, the aforesaid compounds have the serious disadvantage of causing fabric yellowing which is caused by the deposition of yellow color bodies from the rinse water onto the fabric. Color imparted to textiles laundered with cationic softening agents has been found to be related to the amount of softening given to the textiles. That is, with highly colored water supplies, laundered textiles have a greater degree of yellowness or yellow color when a substantial and effective amount of softening agent is used therewith.

Accordingly, it is an object of this invention to provide compositions capable of imparting softness properties to fabrics with a minimal, if any, yellowing normally associated with fabric softening.

It has now been found that fabrics treated with compositions containing quaternary borohydride or, alternatively, quaternary compounds and alkali metal borohydride exhibit the desired degree of softness without the degree of yellowing normally associated with softening agents.

Although sodium borohydride has been used together with detergents in fabric laundering to increase the useful life of fabrics by decreasing the loss in strength of the fabric after repeated washings (US. Pat. No. 3,081,265), it has never been utilized with quaternary ammonium fabric softeners in a textile treating application. The aforesaid quaternary compounds, which are cationic, are incompatible with anionic detergents commonly used in laundering because of reaction or interaction therewith, thereby depleting the detergency action in the washing operation as well as forming precipitates which deposit on the washed articles, giving them an undesirable appearance. Consequently, fabric-softening applications have necessarily been conducted separately, such as after the washing operation, and preferably during the rinsing cycle in the laundering of the fabrics.

The borohydride-containing compositions of this invention comprise either a quaternary compound and an alkali metal borohydride or a quaternary borohydride, the presence of the borohydride anion being responsible for reducing the yellowing of the fabrics due to the presence of the softening agents.

The quaternary compound contemplated by this invention are textile softening agents inclusive of the alkyltrimethyl-ammonium salts where the alkyl group ranges from Cl6 to C24; the dialkyldimethyl-ammonium salts where each of the alkyl groups ranges from C12 to C24; ethoxylated derivatives of quaternary compounds; hydrazinium compounds; and imidazolinium compounds. The general structural formula for the quaternary ammonium compounds may be represented by the following:

wherein X has a value of from one to seven; Y is any anion, inorganic or organic such as halogen (e.g. chloride, bromide, iodide, or fluoride), sulfate, nitrate, phosphate, acetate, methosulfate and equivalents; and at least one of the R groups is a C to C aliphatic group.

The hydrazinium compounds may be represented by the structure-[R, R R NNl-l Y, wherein R, is an aliphatic group containing 16 to 24 carbon atoms, R and R, are alkyl groups, each containing from one to twenty-four carbon atoms, and Y is any anion as defined above.

The imidazolinium compounds may be represented by the following structural formula:

where R is hydrogen or lower alkyl of one to six carbon atoms; R, and R, are independently hydrogen, aliphatic or cycloaliphatic; R is alkyl, substituted alkyl (e.g. hydroxyalkyl, haloalkyl, alkoxyalkyl, cyanoalkyl, etc.); and aralkyl (e.g. benzyl, cinnamyl, etc.); Y represents an anion, organic or inorganic, similarly as in the above quaternary ammonium formula; and at least two of the R groups (i.e. R, R,, R,, and R,,) contain more than 10 carbon atoms. A preferred group of compounds within this class contains at least one C,, moiety or higher for R, and one C,, moiety or higher for R or R Of further preference are compounds wherein R is a substituent of the structure:

m is one to six;

n is two or more, e.g. two to seven; and

R,, is selected similarly as R, and R to yield compounds of the following general formula:

In the above formula, it is most preferred that at least two of the substituents R,, R and R, be alkyl of from 15 to 23 carbon atoms.

Specific examples of suitable quaternary compounds capable of softening textiles are: distearyl dimethyl quaternary ammonium chloride; distearyl dimethyl quaternary ammonium bromide; distearyl dimethyl quaternary ammonium methosulfate; dicoco dimethyl quaternary ammonium chloride; dimethyl arachidyl, behenyl quaternary ammonium chloride; dialkyl dimethyl quaternary ammonium chloride the alkyl groups of which comprise a mixture consisting essentially of 24 parts of hexadecyl, 75 parts of octadecyl and one part of octadecenyl; the latter quaternary compound is also known as dihydrogenated ditallow dimethyl ammonium chloride; hexadecyl trimethyl ammonium chloride; heptadecyl trimethyl ammonium chloride; cetyl trimethyl ammonium chloride; stearyl trimethyl ammonium chloride, etc.

Illustrative imidazolinium compounds include l-(2 -stearoxyethyl)-DQ2-heptadecyl-1benzyl imidazolinium chloride; 1-(2stearoylaminoethyl)2-heptadecyl-lbenzyl imidazolinium chloride; 2-heptadecyl-1-decanoylloctadecyl imidazolinium chloride; l-(2hydroxyethyl)-2-heptadecyl-l-octadecyl imidazolinium bromide; l(2

v st earoyloxethyl)-2-ethyl-1-hexadecyl imidazolinium chloride;

l( N-stearoylaminoethylaminoethyl)-2-heptadecyl-1-ethyl imidazolinium bromide; l-(N-stearoylaminoethyl)1 methyl-Z-stearyl imidazolinium methosulfate; and others as fully described in US. Pat. No. 2,874,074 and British Pat. No. 1,089,010, the compounds of which are incorporated herein by reference.

The term coco"refers to fatty acid groups formed in coconut oil fatty acids. Such acids contain from about eight to 18 carbon atoms per molecule, predominating in C12 to C14 acids.

The alkali metal borohydride may be mixed with the above quaternary fabric softener in the solid state or in a solvent affording mutual solubility and stability, and used in that state. This mixture must be capable of yielding the borohydride anion in solution. A simple borohydride salt such as the alkali metal borohydride, and specifically sodium borohydride, has been found particularly effective when utilizing at least a 1:1 mole ratio of borohydride to quaternary compound. However, the borohydride content may be varied in excess of the 1:1 mole ratio (i.e. borohydride to quaternary). The quaternary salt plus sodium borohydride mixed in situ, inhibits yellowness buildup and retains the soft, fluffy characteristics of the fabric.

The use of a quaternary borohydride in lieu of the mixture of quaternary compound and alkali metal borohydride has been found to be even more effective in the prevention of yellowness buildup, while causing no decrease in softener deposition onto the fabric.

The quaternary borohydrides of the present invention may be illustrated by the following formulas:

1. Long chain monoalkyltriloweralkyl ammonium borohydrides where the long chain alkyl group is C to C and the lower alkyl is C to C 2. Di(long chain)alkyldi(loweralkyl) ammonium borohydries where the long chain alkyl group is C to C and the lower alkyl is C to C 3. Ethoxylated derivatives of quaternary ammonium compounds, generally of the formula;

wherein each of the R groups is, independently, an aliphatic, and preferably and alkyl, chain of from one to 24 carbon atoms, and at least one of the R groups is such a chain at least 12 carbon atoms, and preferably, 16 carbon atoms; and X has a value from one to seven;

4. Hydrazinium borohydries, generally of the formula: [R R R N-Nl-l 1BH4 wherein each of the R groups is, independently, an aliphatic, and preferably, an alkyl, chain of from one to 24 carbon atoms, and at least one thereof is C 5. imidazolinium borohydries:

BHF

wherein R, R,, R and R are as defined above in the description of the imidazolinium salts (i.e. halides,etc);

The preferred imidazolinium borohydries have the formula:

CnHnX CR 2 Ag 4 ditridecyl diCl-l ammonium borohydride; ditetradecyl dimethyl ammonium borohydride; N-( 2-hydroxyethyl)-stearyl dimethyl ammonium borohydride;

N(omega-hydroxyethoxyethyl)-dilauryl ethyl ammonium borohydride; 2-heptadecyl-1-decanoyl-loctadecyl imidazolinium borohydride; l( 2stearoxyethyl)-( 2- 1 -me thyl imidazolinium borohydride; l( N- stearoylaminoethylaminoethyl)-2-heptadecyl-l-ethyl imidazolinium borohydride; l-(2hydroxyethyl)-2-heptadecyl-l-octadecyl imidazolinium borohydride; l(2-palmitoylaminoethyl)-2-ehtyll -hexadecyl imidazolinium borohydride; I-(Z-stearoylaminoethyl)-2-heptadecyl-l -propyl imidazolinium borohydride; l( 2 -stearoylaminoethyl)2-heptadecyl-l-benzyl imidazolinium borohydride.

The quaternary borohydrides are valuable softening agents for textiles and fabrics manufactured from synthetic and natural fibers and blends thereof, inclusive of cellulose, Dacroncotton blends, nylon, wool, cotton, Orlon, Orlon blends and the like. These borohydrides are stable, water-soluble and/or water-dispersible compounds, capable of imparting the desired degree of softness with a minimal, if any, yellowing, when utilized in amounts of from about 0.05 percent to about 1 percent, and preferably, in amounts from 0.1 percent to 0.5 percent by weight of the fabric. The fabric treated with the softening agent is impregnated and coated therewith, the higher dosages being retained on the treated fabrics even after several subsequent washings without treatment to yield a soft, fluffy fabric. Laboratory tests have shown that fabrics treated in accordance with this invention will not yellow with age or with repeated treatment.

These fabric-softening quaternary borohydrides are prepared in any suitable manner. A preferred method constitutes reacting the corresponding quaternary ammonium salt such as the halide with the alkali metal borohydride in the presence of a polar solvent. This reaction proceeds metathetically at low or moderate temperatures in the presence of the solvent. Suitable solvents include; water; liquid organic amines such as triethylamine, trimethylamine, triisopropylamine; aliphatic alcohols such as methyl, ethyl, npropyl, isopropyl, and the butyl alcohols; amides such as for mamide, etc. Nonreactive solvents are preferred, and consequently, when using particularly water, methyl and ethyl alcohols, the reaction medium should be highly alkaline, i.e. pH above 10, to avoid loss of borohydride due to decomposition.

To exemplify a borohydride preparation, dimethyl distearyl ammonium borohydride is prepared by reacting dimethyl distearyl ammonium chloride with sodium borohydride in isopropyl alcohol. The resultant product is a white solid and analyzed as 90 percent of the theoretical borohydride content by acid hydrolysis. Further evidence for the presence of borohydride was afiorded by infrared analysis.

The present invention is more fully described and exemplified in the following examples, wherein parts and percentages are by weight unless otherwise indicated Examplesl and 11 Terry cloth swatches were rinsed in a tergotometer bucket rotating at 100 rpm. and containing 950 ml. of water, 50 ml. of pH bufier and an amount of softening agent to provide lXlO' moles. All rinses were conducted at 100 F. for 5 minutes. A high yellow color water supply from Jersey City and a low one from New Brunswick were employed. The results obtained after one and three cycle treatments are shown in table 1, each number in the table being the average of all swatches exposed to that particular treatment. The swatches were line dried at room temperature and evaluated for softness and yellowness. whiteness values are determined with a Gardner Color Difference Meter, using the +12 scale as a measure of the yellow chromaticity. However, higher b values or whiteness numbers indicate a high amount of yellowness and poor results; whereas low 17 values or whiteness numbers denote less yellowness or greater whiteness and excellent results. A difierence of 0.05 b units in the test represents a difference which is visible to the eye.

Results of the tests, illustrating the use of the new additive compositions in a rinse cycle, are set forth in table 1.

A-Water blank B-Dimethyl distearyl ammonium chloride (IXIO' M) C-Dimethyl distearyl ammonium chloride plus sodium borohydride (each l l0"' "M) D-Dimethyl distearyl ammonium borohydride (1X 1 0"M) Swatches treated with compositions B, C, and D felt equally soft after treatment.

The above table clearly shows the superior results obtained with compositions C and D regarding fabric softening with a decrease in fabric yellowing normally associated with softener formulations.

EXAMPLES III V Terry cloth swatches were treated as in example i, with the dimethyl distearyl ammonium chloride held at a constant 0.4 percent by weight based on the treated fabric, but the concentration of the sodium borohydride being increased. The results are summarized in table [1.

TABLE II Yellowness Cone. of NaBH. Increase (bunits) none L66 The above table clearly shows a decrease in yellowness with an increase in the sodium borohydride concentration.

The swatches remained equally soft, regardless of the borohydride concentration. 5 The new compositions can be packaged in paper, plastic or any other suitable packaging medium or material. For example, the textile softener composition can be packaged in a water soluble plastic material such as polyvinyl alcohol, isotactic polyvinyl methyl ether, etc. for use in a rinse cycle (e.g. of a laundering operation). The present compositions can be in solid form in the character of a free-flowing powder, chips, flakes, granules, tablets and the like or in the form of a solution or dispersion.

The new compositions can be used to treat a variety of fabrics, which can be made from natural animal and vegetable fibers and blends of natural and synthetic fibers as well as entirely from synthetic fibers. These include wool, silk, cotton, linen, glass, acetate, rayon, Dacron, Orlon, blends of Dacron e.g. with cotton, Orlon-wool blends, and the like.

This treatment is especially advantageous where it is desired to overcome harshness of feel or to enhance softness to touch and decrease fabric yellowing. Advantages realized herewith are softer, fluffier towels, smoother, silkier sheets and pillowcases, longer garment life and a whiter and/or brighter fabric.

Although the present invention has been described with reference to particular embodiments and examples, it will be apparent to those skilled in the art that variations and modifications of this invention can be made and that equivalents can be substituted therefor without departing from the principles and true spirit of the invention.

What is claimed is:

l. A method of softening textiles without yellowing which comprises contacting textile materials in the aqueous rinse cycle of a laundering operation with from about 0.05 percent to about 1 percent by weight of a borohydride containing composition consisting essentially of a quaternary borohydride selected from the group consisting of:

A. long chain monoalkyltriloweralkyl ammonium borohydride wherein said long chain alkyl group has from 16 to 24 carbon atoms and said lower alkyl groups have from one to six carbon atoms;

B. dilongchain alkyl dilower alkyl ammonium borohydrides said long chain alkyls have from 12 to 24 carbon atoms and said lower alkyls have from one to six carbon atoms;

ethoxylated derivatives of quaternary compounds represented by the formula wherein R is selected from the group consisting of hydrogen and alkyl groups having from one to six carbon atoms, R,

represents an alkyl group having from 15 to 23 carbon atoms, R is n 2uX)m(HJ 1 wherein n is an integer of from two to six, m is an integer of from one to seven and X is selected from the group consisting of -O- and Nl-land R is selected from the consisting of alkyl and aralkyl substituents.

Claim 2. The method of claim 1 wherein said quaternary borohydride is dimethyl-distearyl ammonium borohydride.

3. A method of softening textiles without yellowing which comprises treating materials in the aqueous rinse cycle of a laundering operation with from about 0.05 percent to about 1 percent by weight of a borohydride containing composition consisting essentially of a quaternary compound and an alkali metal borohydride in a mole ratio of from 1:1 to 1:100 and wherein said quaternary compound is selected from the group consisting of A. quaternary ammonium compounds represented by the formula wherein R and R, are lower alkyl groups having from one to six carbon atoms, R3 an alkyl group containing from 12 to 24 carbon atoms, and R is selected from the group consisting of alkyl groups containing 12 to 24 carbon atoms and an ethoxylated group represented by the formula (Cl-l,Ch2o),l-l

wherein x is an integer of from one to seven, Y is selected from the group consisting of halogen, sulfate, nitrate, phosphate, acetate and methosulfate B. hydrazinium compounds represented by the formula [R R R N-NH ]Y"= wherein R is an aliphatic group containing to carbon atoms, R and R are alkyl groups containing one to 24 carbon atoms and Y is an anion as defined above:

C. imidazolinium compounds represented by the formula wherein R is selected from the group consisting of hydrogen and alkyl groups having from one to six carbon atoms, R, represents an alkyl group having from 15 to 23 carbon atoms,

' R is (CnII2|iX)mfiRl 25 wherein n is an integer of from two to six, m is an integer of from one to seven and X is selected from the group consisting of O and -NH, and R is selected from the group consisting of alkyl and aralkyl substituents.

4. The method according to claim 3 wherein said borohydride composition comprises sodium borohydride and dimethyl distearyl ammonium chloride.

5. The method of claim 3 wherein said borohydride is present relative to the quaternary compound in a 1:1 mol ratio.

r e a 1- 

1. A method of softening textiles without yellowing which comprises contacting textile materials in the aqueous rinse cycle of a laundering operation with from about 0.05 percent to about 1 percent by weight of a borohydride containing composition consisting essentially of a quaternary borohydride selected from the group consisting of: A. long chain monoalkyltriloweralkyl ammonium borohydride wherein said long chain alkyl group has from 16 to 24 carbon atoms and said lower alkyl groups have from one to six carbon atoms; B. dilongchain alkyl dilower alkyl ammonium borohydrides said long chain alkyls have from 12 to 24 carbon atoms and said lower alkyls have from one to six carbon atoms; C. ethoxylated derivatives of quaternary compounds represented by the formula
 3. A method of softening textiles without yellowing which comprises treating materials in the aqueous rinse cycle of a laundering operation with from about 0.05 percent to about 1 percent by weight of a borohydride containing composition consisting essentially of a quaternary compound and an alkali metal borohydride in a mole ratio of from 1:1 to 1:100 and wherein said quaternary compound is selected from the group consisting of A. quaternary ammonium compounds represented by the formula
 4. The method according to claim 3 wherein said borohydride composition comprises sodium borohydride and dimethyl distearyl ammonium chloride.
 5. The method of claim 3 wherein said borohydride is present relative to the quaternary compound in a 1:1 mol ratio. 